Power conversion apparatuses including a converter circuit which converts AC power of an AC power supply to DC power, and an inverter circuit which converts the DC power of the converter circuit to AC power of a predetermined frequency have been known. For example, an example of such a power conversion apparatus has generally been known as disclosed by Patent Document 1, in which a plurality of diodes are bridge-connected to constitute the converter circuit, and a plurality of switching elements are bridge-connected to constitute the inverter circuit.
An example of a method for controlling output of an inverter circuit which controls and drives a motor etc. has been known as disclosed by Patent Document 2, for example. In this example, droop control is performed by detecting current input to the inverter circuit, and reducing an output frequency of the inverter circuit in such a manner that the detected current value does not exceed a predetermined value.